Page 3 of 6 FirstFirst 12345 ... LastLast
Results 21 to 30 of 59

Thread: 50 yard Zero

  1. #21
    Join Date
    Sep 2010
    Posts
    82
    Feedback Score
    0

    Thumbs up The old school way

    I do the old school zero as ra2bach mentioned. Most shooters in this area want a 100 yard zero. So my zero is a little different but the mechanics are just about the same. I use a 1 1/2 blaze orange paste at 100 yard and refer scope to barrel picture. I have a periscope that fits in the chamber for my aging eyes. I would also say that zero is more or less mission/shooter specific and you can't say that one is better then the other. I'm old Corps, and now my shooting days are more of metal and paper targets so I use the old 300 yard zero(scopes and irons, red dot is at 100). But I'm sure it's not what a LEO or CQB guy would want to use.
    To each his own and what gets the job done.

    Stay safe gents.

  2. #22
    Join Date
    Apr 2007
    Location
    FL
    Posts
    9,325
    Feedback Score
    28 (100%)
    I have used 300 yard zeroes (BZOs), 50 yard zeroes, 200 yard zeroes, 100 yard zeroes, and all the above in meters as well.

    For shooting out to 200 meters, I have found the 100 yard/meter zero to be the easiest to deal with as far as hold-overs go if using an optic. You don't have to deal with any hold-unders for the entire trajectory, it is twice as forgiving at close range as far as hold-over goes, has the longest portion of POA/POI, and that POA/POI is at the most relevant threat distance where POA/POI most benefits the shooter. Further, most magnified optics with a BDC or range-relevent elevation adjustments are zeroed at 100, therefore there is more inherent crossover skill when changing between optics/guns.

    A lot of shooters drastically overestimate their effective engagement range with M4 type weapons, or assume that if most threats will be inside 25 yards that a 25 yard zero will make the most sense. Both errors cause the shooter to have to deal with more things to compute when bullets need to find their mark. It's a lot easier to do on a flat range with clearly marked firing lines and distances with mental prep time and low stress. It is a much different problem when in the middle of a gunfight. Weighing zero against zero, and simply numbering pro's against con's does not give sufficient weight to the most pressing and life-threatening aspects. If you can have targets appear at unknown distances between 3 and 100 meters and be able to apply your hold-off to achieve a hit on the CNS without hesitation (and be correct), you and your zero are in harmony. If you can't, or if your hold-offs are tied to numerical distances in your memory, you are not. What it boils down to (to me) is that achieving that harmony is easier with a 100 meter zero than any other.
    Jack Leuba
    Director of Sales
    Knight's Armament Company
    jleuba@knightarmco.com

  3. #23
    Join Date
    Sep 2010
    Posts
    82
    Feedback Score
    0

    Question So many zero's so little time.

    Agree with the harmony bit. Like I said, to each his own. Now let's throw some real world stuff into the mix (I'm not bagging on you Failure2stop so don't flame me) More of a survey, if you would.
    1. Your on ACB, flag goes up and your leaving in 24 hours, your convention infantry. Iron sights. What BZO would you use?
    2. Your a military designated shooter, scope, mill dots. 5.56 or 7.62, you choose. Urban and woodlands BZO?
    3. Your a HRST/ SWAT team member with a AIM POINT. BZO?
    4. Your a hunter in Maine, scope with standard crosshair reticle, 30-06
    BZO?
    5. Your a hunter in Montana, scope, standard crosshair reticle, 338 Federal. BZO?

  4. #24
    Join Date
    Apr 2007
    Location
    FL
    Posts
    9,325
    Feedback Score
    28 (100%)
    First, let's clarify some definitions.

    BZO: Battlesight Zero. This is a sight setting that permits a shooter in full combat gear to hit a man sized target (roughly top of head to knees) from 0 to 300 meters (without accounting for weather effect) while applying a center-mass point of aim. This is pretty much a 300 meter zero, though many will zero at 300 yards out of convenience.

    Zero: Achieving point of aim/point of impact at a specific distance. Purists will say that a Zero includes environmental effect, and that a "True Zero" is the same POA/POI without weather effect accounted for in the optic/sight adjustment. Further, one can Zero at a specific distance but with an impact point other than point of aim in an effort to more closely mirror a different distance's trajectory, but that does not change the fact that the distance involved is not the distance at which one expects to see POA/POI. If you don't put bullets into paper at that distance, you aren't really Zeroed at that distance, regardless of what the Google Machine tells you.

    Anyway, to answer barrelwrench's questions:
    100 meter zero to all.
    Caveats:
    1- There is no conventional US infantry that exclusively uses iron sights. When we used to use them, we used a rough 200 yard zero that was achieved by first zeroing the small aperture at 300 set on 8/3 or 6/3 (small gap), then flipping up the large aperture and confirming POI at 50 meters/yards. It was a sub-optimal approach.

    2- Magnified optics: I will not use a long-range optic without finger-adjustable windage and elevation, and I have solid data so that I can determine range and environmental effect and dial it onto my optic to permit POA/POI out to my effective range or apply mildot-holds to achieve rapid hits. If you have a fixed/tool adjustable adjustments you severely limit yourself and your weapon's caipability at distances past max point blank range, which changes drastically based on cartridge and target size. I am not a subject matter expert on hunting elk/deer/prarie dogs/gophers/etc., so I defer to those that are, but when it comes to human threats, I know what I prefer.
    Jack Leuba
    Director of Sales
    Knight's Armament Company
    jleuba@knightarmco.com

  5. #25
    Join Date
    Mar 2008
    Location
    Fredericksburg, VA
    Posts
    4,931
    Feedback Score
    7 (100%)
    Quote Originally Posted by Failure2Stop View Post
    BZO: Battlesight Zero. This is a sight setting that permits a shooter in full combat gear to hit a man sized target (roughly top of head to knees) from 0 to 300 meters (without accounting for weather effect) while applying a center-mass point of aim. This is pretty much a 300 meter zero, though many will zero at 300 yards out of convenience.
    For those of us that come from the armored realm (tanks, LAVs, Brads, etc), recall the "B" for "battlesight." In the LAR community, BZO or battlesight doesn't refer to a "zero," per se, but a specific range as attributed to a specific ammo at which one could put a specific pip of the reticle on an adversary vehicle and be able to anticipate some sort of strike, be it a catastrophic kill, a mobility kill, an annoyance, or something off of which you could note impacts and shift to achieve one of the previous three.

    In this case, if I went through the specified procedure to attain a 1000m zero, I could hold the battlesight of the reticle at 6 o'clock of mass and expect hits from 0-1450m with APDS-T or 0-950m holding center-mass with HEI-T. See, the "zero" is the same, but the battlesight range varies; it's a general term, one of employment. Maybe call it more of a goal...?

    Hunters, you may be more familiar with ballistic references to "point-blank range," which as I understand it, tells you that given X zero and Y desired impact zone (like, 3" on a groundhog), you can anticipate hits within that specified zone from 0-???? yards (ick!)/meters/furlongs/parsecs, or whatever increment your fevered brain decides is applicable to your desired endstate (a dead critter, I'm guessing). Guess what, guys, if you've been cognizant of your point-blank range, you've been employing a BZO.

    BZO/point-blank range, by definition, will allow you to attain hits on a specified size of strike zone BEYOND your actual zero range. It's a performance envelope, but the term is mis-applied in regard to describing POA/POI at a given range/ammo/barrel/human sacrifice combo.
    Last edited by JSantoro; 10-02-10 at 19:48.
    Contractor scum, PM Infantry Weapons

  6. #26
    Join Date
    Sep 2010
    Posts
    82
    Feedback Score
    0

    Thumbs up ZERO

    I can say that I agree with some of what you both had stated about BZO. Santoro's statement is more to my thinking on PBR and BZO.
    I do have to point out to Failure2stop that the Marine Corps still teaches iron sight in boot camp and OCS. It maybe a world of optics now a days but it don't make iron sight any less important.
    Thank you both for your input and good info.

  7. #27
    Join Date
    Sep 2009
    Location
    South La.
    Posts
    1,893
    Feedback Score
    9 (100%)

    Couple of other Definitions

    .

    In a similar Thread, a few weeks ago, Molon brought up the terms – “Near Zero” and “Far Zero”. I hope this doesn’t add confusion.

    If you sight-in at 50-yards, the bullet should cross the line of sight (LOS) at 50-yards (Near Zero) and again about plus/minus 220 yards. BUT you only have a “Near Zero” at this point. The “Far Zero” is just a guestimate until you actually shoot that guestimated range to verify it.

    If you sight-in at 25-yards, the bullet crosses the LOS at 25-yards and then again around 400+ yards. Again, at this point, you only have a Near Zero.

    The only sight-in range that doesn’t have a “Near Zero” and a “Far Zero” is a 100-yard sight-in because the bullet reaches the LOS right at 100-yards and does not go above the LOS. So, at 100-yards, the bullet grazes the LOS and then starts going to the dirt.

    To have a “Far Zero” you need to shoot at that distant range to verify that the bullet does in fact cross the LOS again at that particular range.

    Now, it has always been my understanding that the BZO (Battlesight Zero) is for doing a quick check of the sight when there is not time or distance to do a proper sight-in. That would fit F2S’s definition of being able to hit “top of the head to the knees”. Is this correct?

    Now...does this make sense...?
    .
    Last edited by ucrt; 10-02-10 at 22:02. Reason: Clarity

  8. #28
    Join Date
    Mar 2008
    Location
    Fredericksburg, VA
    Posts
    4,931
    Feedback Score
    7 (100%)
    No, that's more of a fringe benefit of a near-zero.

    You can use it as a first step to get your zero by ensuring that you're on paper at distance, and you can use it as a means kinda-sorta confirmation of a KD zero already established, so long as you know where it's supposed to print in relation to a like POA as your KD zero.

    Ergo, if you have a 50/200 zero that you've already confirmed @ 200, but you only have a 25yd range to work with and know that your rounds should print about something like 1.25" low at that distance with a center-mass hold, you have a pretty good idea that your zero hasn't changed.
    Contractor scum, PM Infantry Weapons

  9. #29
    Join Date
    May 2009
    Location
    Salt Lake, Utah
    Posts
    55
    Feedback Score
    0
    Looks like I'll be doing a 50yd zero for my rifles from now on. Thanks for the info!

  10. #30
    Join Date
    Apr 2007
    Location
    FL
    Posts
    9,325
    Feedback Score
    28 (100%)
    Quote Originally Posted by barrelwrench View Post
    I do have to point out to Failure2stop that the Marine Corps still teaches iron sight in boot camp and OCS.
    Heh, I am well aware of what the USMC teaches to whom, and how and why they are evaluated in the manner that they are.

    Don't be suprised when evaluating irons for entry level training is no longer the case. Nobody deploys with just irons on their rifles/carbines, so it doesn't make much sense to continue to teach irons when optics are what we do work with.

    RE- Near Zero and Far Zero.
    I have always used the terms "Initial Point" and "Zero Range" to describe the distances at which one achieves POA/POI, since the IP will vary depending on optic height, ammo, muzzle velocity, etc, as well as the fact that just because your ballisitc calculator tells you that if you are 1.5" low at 25 you will be dead on at 100 doesn't mean that when you actually zero at 100 the reverse will be true. For example; my work M4, when zeroed dead-nuts at 100 meters prints about 1" high and 1/2" left from the supposed POI at 25.

    Now, it has always been my understanding that the BZO (Battlesight Zero) is for doing a quick check of the sight when there is not time or distance to do a proper sight-in. That would fit F2S’s definition of being able to hit “top of the head to the knees”. Is this correct?
    No. It is a shortcut that grew into common practice within organizations. The 36 yard/33 meter zero is a Field Expedient BZO, and is intended to get the shooter on the frame at 300. At some point every zeroing exercise started to be referred to as "BZO" within the Corps, and there is a concerted effort by some to get that incorrect definition corrected in the minds of leaders. There is nothing about "Battle" or "Combat" prep that should be expedient or short-cutted. It's one thing to do a field-expedient fix to meet an immediate need, and an entirely different thing to accept that field-expodient fix as acceptable when the option exists to do something the right way, at least when lives are on the line.
    Jack Leuba
    Director of Sales
    Knight's Armament Company
    jleuba@knightarmco.com

Page 3 of 6 FirstFirst 12345 ... LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •